Air from a heating or cooling unit stored in a backpack is blown by a fan into an extendable tube and through a delivery tube to deliver heated or cooled air to wearer. The delivery tube can be run into a hat, helmet, or cap to heat or cool the head of the wearer. Alternatively, the delivery tube can bifurcate to create a yoke from which two perforated delivery tubes extend that run over the shoulders of the wearer beneath their clothes to deliver heated or cooled air. The extendable tube allows the wearer to move freely, turning their head side to side or nodding up and down.